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Class 10 (Old)

Course: Class 10 (Old) > Unit 12

Lesson 3: Frustum of a cone

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Curved surface area of a frustum

Google Classroom

Let's learn how to find the curved surface area of a frustum of a cone through an example. Let's use the intuitive approach rather than directly plugging into the formula. Created by Aanand Srinivas.

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margotb
Posted 2 years ago. Direct link to margotb's post “where did he get the 22/7...”
where did he get the 22/7 from?
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- Leeisha
  Posted 2 years ago. Direct link to Leeisha's post “it's a value of pi”
  it's a value of pi
  Comment on Leeisha's post “it's a value of pi”
  (1 vote)
ljodwyer67
Posted 3 years ago. Direct link to ljodwyer67's post “how did h1 = 8cm. this wa...”
how did h1 = 8cm.
this was not clear how you completed the calculation
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- Jerry Li
  Posted 3 years ago. Direct link to Jerry Li's post “He arrives to h1/h1+4 = 6...”
  He arrives to h1/h1+4 = 6/9 because of proportionality.
  He then cross multiplies and arrives at 9h1 = 6h1+24
  That can be rearranged into 9h1-6h1=24.
  3h1=24
  Then we divide both sides by 3
  3h1/3=24/3
  h1=8
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jane thuo
Posted 3 years ago. Direct link to jane thuo's post “In a certain group member...”
In a certain group members were contributing 2000000 total,if 40 of the members pulled out the remaining members had to contribute 2500 more.How many members were there in the group
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